Energy absorbing propeller shaft for motor vehicles

Abstract

A propeller shaft for motor vehicles, having an intermediate joint provided in the form of an axially movable universal ball joint and consisting of at least an outer joint part with longitudinally extending first ball tracks, an inner joint part with longitudinally extending second ball tracks and torque transmitting balls guided in radially opposed first and second ball tracks, with the outer joint part being firmly connected to a tubular shaft and with the inner joint part being connected to a shaft journal, and with the inner diameter of the outer joint part or of the adjoining tubular shaft in the region adjoining the free space assumed by the inner joint part in operation during plunging movements in the direction of the tubular shaft being smaller than the outer diameter of the inner joint part.

I claim: 
     
       1. A propeller shaft for motor vehicles comprising: an intermediate joint in the form of an axially movable universal ball joint, said intermediate joint including at least an outer joint part with longitudinally extending first ball tracks, an inner joint part with longitudinally extending second ball tracks and torque transmitting balls guided in radially opposed said first and second ball tracks, said outer joint part being firmly connected to a tubular shaft and providing a free space, occupied by the inner joint part in operation during plunging movements in the direction of the tubular shaft, and said inner joint part being connected to a shaft journal, an inner diameter of one of the outer joint part and the adjoining tubular shaft axially adjoining the free space is smaller than an outer diameter of said inner joint part, such that upon plunging movement during a collision, said inner part enters said inner diameter of said outer joint part or tubular shaft deforming said outer joint part or tubular shaft while said outer joint part or tubular shaft absorbing a considerable amount of deformation energy.   
     
     
       2. A propeller shaft according to claim 1 wherein the inner joint part end positioned towards the tubular shaft includes a tapering inner cone. 
     
     
       3. A propeller shaft according to claim 1 wherein a wall of the outer joint part or of the tubular shaft includes an inner conical portion which is tapered in the direction towards the tubular shaft. 
     
     
       4. A propeller shaft according to claim 1 wherein the outer joint part is provided in the form of a plate metal part. 
     
     
       5. A propeller shaft according to claim 1 wherein axial stops are provided for the balls inside the outer joint part, said stops become effective before the inner joint part abuts the outer joint part or the tubular shaft. 
     
     
       6. A propeller shaft according to claim 1 wherein movable or deformable inserts with a predetermined energy absorbing capacity are arranged in the outer joint part. 
     
     
       7. A propeller shaft according to claim 1 wherein movable or deformable inserts with a predetermined energy absorbing capacity are arranged in the tubular shaft. 
     
     
       8. A propeller shaft for motor vehicle comprising: an intermediate joint in the form of an axially movable universal ball joint, said intermediate joint including at least an outer joint part with longitudinally extending first ball tracks, an inner joint part with longitudinally extending second ball tracks and torque transmitting balls guided in radially opposed said first and second ball tracks and being held in a ball cage, said outer joint part being firmly connected to a tubular shaft and said inner joint part being connected to a shaft journal, an inner diameter of one of the outer joint part and the adjoining tubular shaft axially adjoining a free space, occupied by the ball cage in operation during plunging movements in the direction of the tubular shaft, is smaller than an outer diameter of the ball cage, and stop elements are provided for delimiting the axial movement between the inner joint part and the ball cage, such that upon plunging movement during a collision, said ball cage enters said inner diameter of said outer joint part of tubular shaft deforming said outer joint part or tubular shaft while said outer joint part or tubular shaft absorbing a considerable amount of deformation energy.   
     
     
       9. A propeller shaft according to claim 8 wherein stops for the ball cage are provided in the outer joint part, said stops become effective before the inner joint part abuts the outer joint part of the tubular shaft. 
     
     
       10. A propeller shaft for motor vehicles comprising: an intermediate joint in the form of an axially movable universal ball joint, said intermediate joint including at least an outer joint part with longitudinally extending first ball tracks, an inner joint part with longitudinally extending second ball tracks and torque transmitting balls guided in radially opposed said first and second ball tracks, said outer joint part being firmly connected to a tubular shaft and said inner joint part being connected to a shaft journal, internal dimensions of one of the outer joint part and the adjoining tubular shaft axially adjoining a distance, covered by the balls in operation during plunging movements in the direction of the tubular shaft, are smaller than the outer contour of the balls in the entirety, and stop elements are provided for delimiting the axial movement between the balls and the inner joint part, such that upon plunging movement during a collision, said balls enter said inner diameter of said outer joint part or tubular shaft deforming said outer joint part or tubular shaft while said outer joint part or tubular shaft absorbing a considerable amount of deformation energy.